当我在代码中放入 while 循环时，JavaFX GUI 不会运行，但在删除时会运行

Question

所以我目前正在 javaFX 中制作一个简单的回合制游戏，但遇到了问题。我试图在代码中放入一个 while 循环(在倒数第二个代码块中找到)，但是当我执行程序时没有任何东西可以运行。我没有收到任何错误，也没有弹出窗口。

如果我去掉 while 循环，那么 GUI 就可以正常运行。

我尝试移动 while 循环，但这并没有改变任何东西。我还尝试转到以前的版本，看看 while 循环是否可以在那里工作，但同样的问题也发生了。

package application;

import javafx.scene.image.*;
import javafx.application.Application;
import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.Group;
import javafx.scene.paint.Color;
import javafx.scene.shape.*;
import javafx.scene.text.Font;
import javafx.scene.text.FontPosture;
import javafx.scene.text.FontWeight;
import javafx.scene.text.Text;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Pos;
import javafx.scene.control.Button;
import javafx.scene.layout.FlowPane;
import javafx.scene.layout.Pane;
import javafx.scene.layout.StackPane;
import javafx.scene.media.Media;
import javafx.scene.media.MediaPlayer;



public class Game extends Application {
    Button start, battle, attack, defend;
    Scene intro, beginBattle, standby;
    MediaPlayer mediaPlayer;

    int monsterHealth = 100;
    int playerHealth = 100;

    public void start(Stage primaryStage) {
        primaryStage.setTitle("Dungeon Crawler"); // Gives the title to the window.
        primaryStage.setResizable(false); // Prevents the window from being resized.

        Rectangle rectDungeon = new Rectangle(75, 15, 650, 125); // creates a Rectangle object that consists of the following parameters: X, Y , WIDTH, HEIGHT.
        rectDungeon.setStroke(Color.WHITE); // Colors the borders of the rectangle white. 
//      
//      Media musicFile = new Media("file:Night%20Cave.mp3");
//      mediaPlayer = new MediaPlayer(musicFile);
//      mediaPlayer.setAutoPlay(true); // Sets the music to start as soon as the program runs.     NOTE: TRYING TO GET A MP3 FILE IN AND WHENEVER I USE THIS IT CAUSES THE PROGRAM TO NOT RUN. 
//                                                                                                 NEED TO FIGURE SOMETHING OUT.

        // Sets up the button that will be used 
        // to start the game when it runs.
        start = new Button();
        start.setText("Start");

        start.setOnAction(e -> primaryStage.setScene(beginBattle)); // Sets the button to activate an event handler for the next scene (beast battle starts).
        start.setLayoutX(360); // Sets the x axis location of the button.
        start.setLayoutY(720); // Sets the y axis location of the button.

        Image dungeonImage = new Image("file:Dungeon.png"); // Sets the image object as an image of a door.
        ImageView dungeonView = new ImageView(); // Sets up an object of the ImageView class.
        dungeonView.setImage(dungeonImage); // sets the image of the door to be viewed in the GUI

        // Dialogue initializing the player to what their task is.
        Text dungeonText = new Text("                           You traverse the sewers of your city. "
                + "\n You heard of a monster who lurked here and took a quest to destroy it. "
                + "\n           Worrying for the safety of the citizens you now search for it."
                + "\n     Suddenly, you hear a growl and see a mass bellowing towards you.");

        dungeonText.setFont(Font.font("Sans serif", FontWeight.NORMAL, FontPosture.ITALIC, 20)); // Sets the text as Sans serif with no bolding, italics, and a size of 20
        dungeonText.setStyle("-fx-fill: white;"); // Sets the text with the color white.
        dungeonText.setLayoutX(90); // Sets the x axis location of the text.
        dungeonText.setLayoutY(40); // Sets the y axis location of the text.

        Pane root = new Pane(); // Sets an object to collect all items for the GUI for the scene in question.
        root.getChildren().addAll(dungeonView, rectDungeon, dungeonText, start); // Collects the items needed in the scene.
        intro = new Scene(root, 788, 788); // Sets up the GUI items, and the window size.

//-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------       

        Rectangle rectMonsterDungeon = new Rectangle(75, 15, 650, 65); // X, Y , WIDTH, HEIGHT ------------> CHANGE COMMENT
        rectMonsterDungeon.setStroke(Color.WHITE);

        // Sets up the button that will be used 
        // to move forward if in a one way hall.
        battle = new Button();
        battle.setText("Battle!");

        battle.setOnAction(e -> primaryStage.setScene(standby)); // Sets the button to activate an event handler for the next scene (a hallway).
        battle.setLayoutX(355); // Sets the x axis location of the button.
        battle.setLayoutY(720); // Sets the y axis location of the button.

        Image monsterDungeonImage = new Image("file:MonsterDungeon.png"); // Sets the image object as an image of a one way hallway.
        ImageView monsterDungeonView = new ImageView(); // Sets up an object of the ImageView class.
        monsterDungeonView.setImage(monsterDungeonImage); // sets the image of the one way hallway to be viewed in the GUI

        // Dialogue warning the player of possible dangers 
        // ahead when they enter the first room of the crypt.
        Text monsterDungeonText = new Text("                The beast has reared it's ugly head in front of you!"
                + "\n                              Prepare to battle or else perish!");

        monsterDungeonText.setFont(Font.font("Sans serif", FontWeight.NORMAL, FontPosture.ITALIC, 20)); // Sets the text as Sans serif with no bolding, italics, and a size of 20
        monsterDungeonText.setStyle("-fx-fill: white;"); // Sets the text with the color white.
        monsterDungeonText.setLayoutX(90); // Sets the x axis location of the text.
        monsterDungeonText.setLayoutY(40); // Sets the y axis location of the text.

        Pane root2 = new Pane(); // Sets an object to collect all items for the GUI for the scene in question.
        root2.getChildren().addAll(monsterDungeonView, rectMonsterDungeon, monsterDungeonText, battle); // Collects the items needed in the scene.
        beginBattle = new Scene(root2, 800, 800); // Sets up the GUI items, and the window size.

//----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

while(playerHealth > 0 && monsterHealth > 0) {  
        Rectangle rectMonsterDungeonStandby = new Rectangle(75, 15, 650, 65); // X, Y , WIDTH, HEIGHT ------------> CHANGE COMMENT
        rectMonsterDungeonStandby.setStroke(Color.WHITE);

        Rectangle rectPlayerBoxSB = new Rectangle(140 , 650, 500, 125);
        rectPlayerBoxSB.setStroke(Color.WHITE);

        // Sets up the button that will be used 
        // to move forward if in a one way hall.
        attack = new Button();
        attack.setText("Attack!");

        attack.setOnAction(e -> primaryStage.setScene(intro)); // Sets the button to activate an event handler for the next scene (a hallway).
        attack.setLayoutX(300); // Sets the x axis location of the button.
        attack.setLayoutY(720); // Sets the y axis location of the button.

        // Sets up the button that will be used
        // to defend against the monster if the player 
        // wished to block all or most damage from the 
        // monster.
        defend = new Button();
        defend.setText("Defend!");

        defend.setOnAction(e -> primaryStage.setScene(standby));
        defend.setLayoutX(410);
        defend.setLayoutY(720);

        Image monsterDungeonImageSB = new Image("file:MonsterDungeonSTANDBY.png"); // Sets the image object as an image of a one way hallway.
        ImageView monsterDungeonViewSB = new ImageView(); // Sets up an object of the ImageView class.
        monsterDungeonViewSB.setImage(monsterDungeonImageSB); // sets the image of the one way hallway to be viewed in the GUI

        // Dialogue warning the player of possible dangers 
        // ahead when they enter the first room of the crypt.
        Text monsterDungeonTextSB = new Text("                               Choose from the options below."
                + "\n                                      The Beast's Health: " + monsterHealth);

        monsterDungeonTextSB.setFont(Font.font("Sans serif", FontWeight.NORMAL, FontPosture.ITALIC, 20)); // Sets the text as Sans serif with no bolding, italics, and a size of 20
        monsterDungeonTextSB.setStyle("-fx-fill: white;"); // Sets the text with the color white.
        monsterDungeonTextSB.setLayoutX(90); // Sets the x axis location of the text.
        monsterDungeonTextSB.setLayoutY(40); // Sets the y axis location of the text.

        Text playerTextSB = new Text("Which will you do?"
                                    + "\n     Health: " + playerHealth);
        playerTextSB.setFont(Font.font("Sans serif", FontWeight.NORMAL, FontPosture.ITALIC, 20));
        playerTextSB.setStyle("-fx-fill: white");
        playerTextSB.setLayoutX(310);
        playerTextSB.setLayoutY(685);

        Pane root3 = new Pane(); // Sets an object to collect all items for the GUI for the scene in question.
        root3.getChildren().addAll(monsterDungeonViewSB, rectMonsterDungeonStandby, rectPlayerBoxSB, monsterDungeonTextSB, playerTextSB, attack, defend); // Collects the items needed in the scene.
        standby = new Scene(root3, 800, 800); // Sets up the GUI items, and the window size.
}

//-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------       


        primaryStage.setScene(intro); // Sets the first scene in the GUI as the DOOR.png with its accompanying text and button.
        primaryStage.show(); // Shows the GUI to the user and provides the different scenes in the program
                             // depending on the button choices the user makes.
    }
    public static void main(String[] args) {
        launch(args);
    }
}

我希望 GUI 能够像 while 不存在一样运行，因为playerHealth 和 monsterHealth 最初都设置为大于 0。

相反，我没有弹出 GUI 窗口，也没有出现错误。

Answer 1

您的期望完全错误。你写:

I'm expecting the GUI to run just as if the while was not there since both playerHealth and monsterHealth are initially set greater than 0.

但是 while 循环条件正好相反:

while(playerHealth > 0 && monsterHealth > 0) {  

对于您的初始条件，此循环将永远运行，从而永远阻止 JavaFX 应用程序线程。